This device generally relates to threaded tamper evident container closures, and to threaded tamper-evident closures having a push-pull resealable tamper evident pour spout.
Examples of threaded prior art tamper-evident closures are disclosed in U.S. patent application Ser. No. 08/332,589 filed Oct. 31, 1994 which is the priority document for International Patent Application No. PCT/IB95/01174 (published Jul. 11, 1996 under International Publication No. WO 96/20872), U.S. Pat. Nos. 4,664,278 and 4,971,212, and in U.K. Patent No. GB 2,177,384 and French Patent No. 2,682,357. Examples of threaded prior art tamper-evident closures having a push-pull resealable tamper-evident pour spout are disclosed, in U.S. patent application Ser. No. 08/332,140 filed Oct. 31, 1994 which is the priority document for International Patent Application No. PCT/IB95/01105 (published May 9, 1996 under International Publication No. WO 96/13442), and in U.S. Pat. No. 5,465,876.
The present invention provides an improved means of locking threaded tamper-evident closures to a bottle neck, by means of a uniquely shaped annular flange extending radially inward from the inner surface of the tamper-evident band attached to the bottom edge of the closure body. This flange, which can be continuous or segmented, can for example form an upwardly angled xe2x80x9chookxe2x80x9d shaped surface for engaging the sealing flange on the bottle neck. The hook-like flange has a reverse basis that allows it to slide past the bottle neck sealing flange as the cap is snapped downward onto the container during installation. The hook-shaped flange then provides a positive grip on the bottle neck sealing flange to prevent removal of the closure while the tamper evident band remains intact. This hook-like sealing feature makes the closure of the present invention more difficult to detach from the container neck than existing prior art designs to minimize the risk of unintended removal while at the same time providing the same ease of installation as found in existing designs. The hook-shaped flange of the present invention can optionally be configured with a plurality of fins or gussets extending upwardly from and in a direction substantially perpendicular to the sealing surface of the flange. The purpose of the fins or gussets is to assist in breaking and dislodging the tamper-evident band from the remainder of the closure by engaging the exterior surface of the bottle neck as the tamper-evident seal is being broken.
Additionally, the present invention provides a novel configuration for protecting the integrity of frangible elements during installation of threaded tamper-evident closures. A plurality of elevated areas extend upwardly from the tamper-evident band in spaced relation to the bottom edge of the closure body. The purpose of these elevated areas is to support the tamper evident band in resisting vertical movement imparted by insertion of the closure on the bottle neck, thereby protecting the frangible elements during assembly. The frangible elements connecting the tamper-evident band to the lower edge of the closure body may be configured to extend from these elevated areas as well as the non-elevated areas of the tamper-evident band. The purpose of attaching frangible elements to the elevated areas of the tamper-evident band is to assist in preventing axial misalignment of the tamper-evident band relative to the annular depending skirt portion of the closure upon subjecting the closure to torquing forces during assembly to the container neck.
Prior art threaded push-pull pour spout closures providing tamper evidency and having tamper evident pour spouts have not always been leak proof at spout closure interface. Generally, prior art push-pull pour spout closures that are reusable do not provide effective sealing at the juncture between the spout opening and the plug positioned in the opening when the spout is closed. Because of the very small diameter of the opening and the concern for safety, it is not possible to add non-integrated sealing means. The present invention solves this problem by utilizing a closure plug which combines a circular closure disk with an integral annular skirt depending from the periphery of the disk thereby defining a hollow cavity for the plug interior and increasing the structural flexibility of the plug. The increased structural flexibility provided by the hollow cavity causes inward deformation of the plug skirt upon engagement with annular flanges integrated into the periphery of the spout closure central opening to create a form-fitting leak tight seal. A plurality of circumferentially spaced dimples optionally extend from the exterior wall of the pour spout. These dimples facilitate breaking the frangible elements connecting the tamper evident band to the push-pull pour spout closure.
The present invention also optionally provides a tamper-evident dust cover which encloses the push-pull pour spout closure when inserted on the container. The dust cover is provided with a tamper-evident sealing band which remains intact upon initial installation of the dust cover onto the container and which is broken when the dust cover is initially disturbed. The purpose of the dust cover is to provide an indication of whether the push-pull pour spout closure has been exposed subsequent to the sealing of the container.
Accordingly, it is an object of the present invention to provide a threaded tamper-evident closure having an annular hook-shaped flange extending radially inward from the inner surface of the tamper-evident band attached to the bottom edge of the closure body, for locking the closure to a bottle neck while the tamper evident band is intact.
It is a further object of the present invention to provide a threaded tamper-evident closure having an annular hook-shaped flange with a plurality of fins or gussets extending upwardly from and in a direction substantially perpendicular to the sealing surface of the flange, to assist in breaking and dislodging the tamper-evident band from the remainder of the closure.
It is a further object of the present invention to provide a threaded tamper-evident closure having frangible elements attached from and between a plurality of elevated areas extending upwardly from the tamper-evident band, for protecting the integrity of frangible elements during installation of the closure on a bottle neck.
It is a further object of the present invention to provide a threaded tamper-evident closure with a reusable push-pull pour spout having a closure plug of increased structural flexibility to provide a more effective leak tight seal.
It is a further object of the present invention to provide a dimple means for facilitating the breakage of frangible elements on the tamper evident band of the push-pull pour spout closure.
It is a further object of the present invention to provide a threaded tamper-evident closure with a reusable push-pull pour spout that utilizes an upwardly angled hook-shaped annular flange to prevent removal of the closure body from a bottle neck while the tamper evident band remains intact.
It is a further object of the present invention to provide a threaded tamper-evident closure with a reusable push-pull pour spout having a plurality of fins or gussets extending upwardly from and in a direction substantially perpendicular to the sealing surface of an annular hook-shaped flange, to assist in breaking and dislodging the tamper-evident band from the remainder of the closure body.
It is a further object of the present invention to provide frangible elements attached from and between a plurality of elevated areas extending upwardly from the tamper-evident band, for protecting the integrity of frangible elements during installation of the closure on a bottle neck.
It is a further object of the present invention to provide a dust cover with a ratcheted tamper-evident sealing band which encloses the push-pull pour spout closure when inserted on the container.
A first preferred embodiment of the present invention generally provides a threaded tamper-evident closure having an annular hook-shaped flange extending radially inward from the inner surface of the tamper-evident band attached to the bottom edge of the closure body. The hook-shaped flange can be continuous or segmented and can for example form an upwardly angled surface for engaging the sealing flange on the bottle neck. The edge of the flange preferably lies at an angle with a plane normal to the inner surface of the tamper-evident band, thereby defining a grooved xe2x80x9chookxe2x80x9d which slides over the locking flange on the bottle neck when the closure is placed on the container but which engages and locks the closure to the container neck when removal of the closure is attempted with the tamper-evident band intact. The hook-shaped flange can optionally be configured with a plurality of fins or gussets extending upwardly from and in a direction substantially perpendicular to the sealing surface of the flange. A plurality of elevated areas extend upwardly from the tamper-evident band in spaced relation to the bottom edge of the closure body. The frangible elements connecting the tamper evident band to the lower edge of the closure depending annular flange may be configured to extend from these elevated areas as well as the non-elevated areas of the tamper-evident band.
A second preferred embodiment of the present invention provides a threaded tamper-evident plastic closure having a tamper-evident band containing the above-described features, for use with a tamper evident push-pull resealable pour spout which is substantially leak proof. The push-pull pour spout has an opening which is partially closed by a second top having a secondary opening therein and a plug spaced thereabove with upwardly angled legs formed integrally with the closure. The plug takes the form of a circular closure disk having an integral annular skirt depending from the periphery of the disk that attaches the plug to the angular legs thereby defining a hollow cavity for the plug interior and increasing the structural flexibility of the plug. Integrated into the periphery of the secondary opening is at least one and preferably two annular flanges which engage the plug skirt when the secondary opening is closed to seal the spout. The annular flanges cause inward deformation of the plug skirt upon engagement to create a form-fitting leak proof seal. A plurality of circumferentially spaced dimples optionally extend from the exterior wall of the pour spout. These dimples facilitate breaking the frangible elements connecting the tamper evident band to the spout closure. The present invention also optionally provides a tamper-evident dust cover which encloses the push-pull pour spout closure when inserted on the container. The dust cover is provided with a ratcheted tamper-evident sealing band which remains intact upon initial installation of the dust cover onto the container and which is broken when the dust cover is initially disturbed.